Bag construction



Feb. 27, 1945. w. s. BREDE ETAI.

BAG CONSTRUCTION Filed July 9, 1945 2 Sheets-Sheet 1 fnveniors fl i'lla/mifirede Mir/Zea Czaris jozmj Feb. 27, 1945. w -s BREDE ETA]? I 2 370326 BAG CONSTRUCT ION Filed Jul s, 194s 2 Sheets-sheet 2 Patented Feb. 27, 1945 BAG CONSTRUCTION William S. Brede, Manley M. Curtis, and John L. Reibold, Minneapolis, Minn., assignors to Brede Inc, Minneapolis, Minn., a. corporation of Minnesota Application July 9, 1943, Serial No. 494,030

4 Claims.

This invention relates to wrappers formed of sheet material and more particularly to wrappers which can be constructed with a heat sealing material so that various sections of the wrapper can be sealed together and also in order that a base piece or closure can be conveniently sealed to the body or" the wrapper.

In making v rappers for devices such as heavy machine c sirnilar units where such parts cted from dust and moisture it is ghtly sealed wrapping device he case of small easily handled tively simple matter to wrap and apply sealing means to h the case of relatively heavy the like where lifting and turnessary srovid cult to properly seal wrapdevices or articles. eject of our invention to provide a machine or other device he- .erein it can he easilyappiied article and effectively sealed to prevent e of moisture and dust to the interior.

e specifically it is an object of the invention to provide a wrapper having sides, tops and ends wherein the sides and ends are flared outwardly to provide a :tlange which is adapted to be sealed to a base sheet, the base sheet having previously been placed beneath the article to be wrapped and extending outwardly along the edges thereof so that the flange formed along the bottom of the main body portion will coincide substantially with the edges of the base sheet.

It is a further object to provide a wrapperoi the type described wherein the outwardly flared portion or flange is continuous and unbroken entirely around the main body of the wrapper.

Still another object of the invention is to provide a wrapper having specially formed end walls which permit the outward bending of the lower portions of the sides and ends to provide a flange which is continuous around the main body ofthe wrapper.

Still a further object of the invention is to provide a method for forming a wrapper such as described above. 1

These and other objects andadvantages of the invention will more fully appear from the following description made in connection with the accompanylng drawings, wherein like reference iii characters refer to the same parts throughout the views, and, in which:

Fig. 1 is a perspective View of a completely assembly wrapper formed in accordance with the invention;

Fig. 2 is a plan view of the main body of the wrapper folded fiat along the longitudinal center thereof; a

Fig. 3 is a plan view of the blanks from which the main body of the wrapper is formed;

Fig. 4 is a fragmentary plan view of aportlon of the main body panel with one end wall secured thereto;

Fig. 5 is an enlarged section taken on the line 55 of Fig. 4;

Fig. 6 is an elevation of the structure shown in Fig. 4;

Fig. 7 is a plan View 01 the bottom or base sheet of the wrapper;

Fig. 8 is an enlarged fragmentary perspective or the lower corner construction; and

Fig. 9 is an end elevation of modified form or construction.

The wrapper includes aynain body portion generally indicated at ill. The body formed principally from a rectangular sheet ll illustrated in Figs. 2 and 3. This sheet includes the wrapper body side portions l2 and top 53. The body also includes end members id.

The top and side sheet ll is shown in Fi 3 to be rectangular. The end members M are formed with straight sides and opposite side portions it? which diverge from the longitudinal center of the end sheets 54 outwardly toward the ends of said sheets. The various parts of the wrapping device are connected together by heat sealing. This is accomplished by the use of one of several types of sheet material well known in the packaging art. time such material is known as Reynolds metal foil packaging material, produced by Reynolds Metal Company, Harrison, New Jersey. It is a laminated kraft having a foil surface treated with a cellulose derivative. When two foil surfaces are brought together under heat and pressure they seal themselves.

As stated above the wrapper end sections I4 are provided with diverging edge portions I 6 in the form of a. shallow V-shaped cut-out. It is necessary to straighten the V-shaped edge I6 in order that it can be bonded with'the straight edge l I a of the main body panel I I. To straighten the edge IS a gather I1 is formed across the center of the end section l4 producing a fold best illustrated in Fig. 5. When the gather I1 is made the V-cut edge l6 assumes a straight line position, as

shown in Fig. 4, and the normally straight edge l assumes a shallow V-shape, the ends ill of the end strip l5 being slanted inwardly as shown in Fig. 4. The end strip 14 is laid over the main body panel I l, as in Fig. 4, and the overlying edges of the end strip l4 and body panel H are connected by running them between heat sealing rollers to provide a clamped and sealed edge seam ISI. This, of course, is done along the longitudinal side edges of the main body panel I I.

The partially assembled body unit comprising the main body panel H and two end sections I4 is then folded along a line which would extend between the two gathers I! in the end sections H, as viewed in Fig. 3, and this folding operation brings the two halves of each end section side edge [5 together and they are united to form a central end seam 20, as shown in Fig. 2. Thus a roughly cup-like or envelope-like unit is produced.

Referring to Fig. 1 the'body side panels l2 are spread apart and the top 13 is generally flattened. This draws the vertical center end seam inwardly. A peak 2| is produced in the top of each end section l4 and this peak is folded down flat against the remainder of the end section, as indicated in Fig. 1.

The wrapper is provided with a base or bottom panel 22 shown in Fig. 7. The base panel 22 is placed over a wooden or other suitable base 23 upon which the article to be Wrapped is positioned. The main body Ill of the wrapper including the top, side and end walls is slipped over the article and the lower edges of the side and end walls are then bent outwardly to provide a flange 24 which is continuous around the bottom of the body and whose outer edge is substantially in registration with the edges of the base panel 22. It is the cutting and assembly of the end panels M with the side panels l2 and top l3 which permit the formation of the outwardly extending flange 24 at the bottom of the wrapper. This feature is important since an ordinary envelope construction will not permit the outward bending or flaring of a flange at the bottom to coincide with the outer edges of the base sheet or panel 22. Fig. 8 indicates a typical lower corner construction. The sealed seam 19 connects the adjacent edges of the side walls 12 and end sections M. The lower portion of each sealed seam I9 i folded upon itself and substantially flat against the flange 23 as indicated at 25. A heated seam sealing machine can then be moved along the edges of the flange '24 and the bottom panel 22 forming a sealed,

clamped union or seam Mi-between the flange 2 and said base panel 22.

In Fig. 9 there-is shown an end elevation of a wrapper utilizing a modified form of end construction. In this case the end panel 21 is formed with lower outwardly flared corner portions 28, the upper and side edges of the end panel being suitably secured to the ends of a main body panel which is of rectangular shape similar to the above described main body panel 10. The sid edge portions of the main panel are curved outwardly to follow the contour of the flared portion 28 on the end panel 21. A flange is formed by pressing the lower edge of the body panel fiat and bending the lower portion of the end panel l4 inwardly .and downwardly approximately from the bottom of said body panel to the dotted line 29. This provides a continuous flange entirely around the wrapper body to produce the same result as that in the first mentioned embodiment. Naturally, a base panel is utilized with this construction, said base panel being conveniently secured to the flange at the bottom of the body portion of the wrapper by suitable means such as heat sealing.

While other types of wraps have been made with a folded heat sealing sheet material the present construction and method of producing the same is one which provides a continuously outwardly extending flange or flare at the bottom of the body of the wrapper so that a continuous seal can be made around the bottom where it joins the base panel, and the wrapper is produced from only four rather regularly cut pieces. The arrangement of the end walls and their assembly with the main body panel I l presents straight line seams to be heat sealed so that they can be run through a conventional linear heat sealing machine. While the wrapper shown in Fig. 1 results in the production of a peak such as the peak 2| in the end walls it is comparatively small as compared to the extra folds or peaks which are produced in other types of wrappers. It should be noted that the wrapper and construction shown in Fig. 9 produces a continuous flange to be attached to the base sheet to form a continuous seal as in the case of the construction in Fig. 1, and it should further be noted that the structure in Fig. 9 is one which eliminates the formation of a peak such as mentioned above. Furthermore, with an ordinary envelope shape of wrapper it is impossible to produce a continuous outwardly extending flange. An envelope type of construction must be split at the corners of the flange and an additional sealing flap or strip must be provided.

It will, of course, be understood that various changes may be made in the form, details, arrangement and proportions of the various parts without departing from the scope of our invention.

What we claim is:

l. A method of forming wrapping devices from sheet material which includes, forming side and top sections, preparing end sheets, each of which is formed with a substantially straight side edge and an opposite side edge diverging outwardly toward the ends of said end sheet, gathering said sheet adjacent its straight side edge to straighten out said divergently formed side edge, connecting said straightened divergently formed edge of said end piece to the edges of said side and top portions, folding said side and top portions and said end sheet to bring the two halves of the straight side of said end sheet together and connecting said halves of said side.

2. The method in claim 1 and bending the lower edges of said sides and ends outwardly to provide a flange, and securing said outwardly bent flange to a base member.

3. A wrapping device comprising, a main body portion including side walls and end walls, said end walls having generally vertical side edges throughout most of their lengths and spreading outwardly and downwardly adjacent their lower ends to provide an outward flare to provide an end wall base portion of greater width than the remainder of said end wall, the side edges of said end wall being secured to adjacent edges of said side walls, the lower edges of said side walls being bent outwardly to provide a flange approximately as wide as the extent of said widened lower portion of said end wall, said end wall at its widened lower portion being bent outwardly to provide a flange portion which constitutes a continuation of said side wall flanges, and a base sheet secured to said side and end wall flange portions to provide a continuous bottom closure for said body portion.

4. A wrapping device comprising, a main body portion having generally vertical sets 01' side and said walls, and a base sheet of a size substantially end walls made of a flexible non-elastic sheet maco-extensive with the outer dimensions of said terial, said walls being secured to each other along flange, said base sheet and flange being connected adjacent edgesmne set of said walls being widened by a continuous seal.

at the vertical lower portion thereof to permit 5 WILLIAM S: BREDE. outward horizontal bending of the free lower MANLEY M. CURTIS. edges of all of said walls and producing a con- JOHN L. REIBOLD. tinuous horizontal flange about the bottoms of 

